/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.naming.factory.webservices;

import javax.xml.namespace.QName;
import javax.xml.rpc.Service;
import javax.xml.rpc.ServiceException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.rmi.Remote;
import java.util.Hashtable;
import java.util.Iterator;

/**
 * Object proxy for Web Services.
 *
 * @author Fabien Carrion
 */

public class ServiceProxy
		implements InvocationHandler {

	/**
	 * changing behavior to method : Service.getPort(QName, Class)
	 */
	private static Method portQNameClass = null;
	/**
	 * changing behavior to method : Service.getPort(Class)
	 */
	private static Method portClass = null;
	/**
	 * Service object.
	 * used for delegation
	 */
	private Service service = null;
	/**
	 * PortComponentRef list
	 */
	private Hashtable<String, QName> portComponentRef = null;

	/**
	 * Constructs a new ServiceProxy wrapping given Service instance.
	 *
	 * @param service the wrapped Service instance
	 * @throws ServiceException should be never thrown
	 */
	public ServiceProxy(Service service) throws ServiceException {
		this.service = service;
		try {
			portQNameClass = Service.class.getDeclaredMethod("getPort", new Class[]{QName.class, Class.class});
			portClass = Service.class.getDeclaredMethod("getPort", new Class[]{Class.class});
		} catch (Exception e) {
			throw new ServiceException(e);
		}
	}

	/**
	 * @see InvocationHandler#invoke(Object, Method, Object[])
	 */
	@Override
	public Object invoke(Object proxy, Method method, Object[] args)
			throws Throwable {

		if (portQNameClass.equals(method)) {
			return getProxyPortQNameClass(args);
		}

		if (portClass.equals(method)) {
			return getProxyPortClass(args);
		}

		try {
			return method.invoke(service, args);
		} catch (InvocationTargetException ite) {
			throw ite.getTargetException();
		}
	}

	/**
	 * @param args Method call arguments
	 * @return Returns the correct Port
	 * @throws ServiceException if port's QName is an unknown Port (not defined in WSDL).
	 */
	@SuppressWarnings("unchecked")
	private Object getProxyPortQNameClass(Object[] args)
			throws ServiceException {
		QName name = (QName) args[0];
		String nameString = name.getLocalPart();
		Class<?> serviceendpointClass = (Class<?>) args[1];

		for (Iterator<QName> ports = service.getPorts(); ports.hasNext(); ) {
			QName portName = ports.next();
			String portnameString = portName.getLocalPart();
			if (portnameString.equals(nameString)) {
				return service.getPort(name, serviceendpointClass);
			}
		}

		// no ports have been found
		throw new ServiceException("Port-component-ref : " + name + " not found");
	}

	/**
	 * @param portComponentRef List
	 */
	public void setPortComponentRef(Hashtable<String, QName> portComponentRef) {
		this.portComponentRef = portComponentRef;
	}

	/**
	 * @param args Method call arguments
	 * @return Returns the correct Port
	 * @throws ServiceException if port's QName is an unknown Port
	 */
	private Remote getProxyPortClass(Object[] args)
			throws ServiceException {
		Class<?> serviceendpointClass = (Class<?>) args[0];

		if (this.portComponentRef == null)
			return service.getPort(serviceendpointClass);

		QName portname = this.portComponentRef.get(serviceendpointClass.getName());
		if (portname != null) {
			return service.getPort(portname, serviceendpointClass);
		} else {
			return service.getPort(serviceendpointClass);
		}
	}

}
